Objective: To develop a Spanish version of the international Hip Outcome Tool questionnaire (iHOT-12Sv) for assessing the psychometric characteristics (internal consistency, convergent validity, test−retest reliability, and floor and ceiling effects) of this version in physically active patients with hip pain. Methods: After conducting the translation and transcultural adaptation, a consecutive sample of patients with labral tear injury and/or femoroacetabular impingement (Pincer or Cam type) were recruited in a Spanish Hospital. Patients completed the iHOT-12Sv and the Spanish version of the iHOT-33 and the Hip Outcome Score (HOS). Internal consistency was calculated using Cronbach’s alpha; convergent validity was evaluated using Spearman correlation coefficients (Rho) with iHOT-33 and HOS; test−retest reliability was examined using the intraclass correlation coefficient (ICC), standard error of measurement (SEM), and minimal detectable changes (MDC); and floor and ceiling effects were calculated as the percentage of patients who obtained the minimum and maximum score. Results: One hundred and fifty-three patients (64.7% males) participated in this study. Cronbach’s alpha of 0.92 revealed the excellent internal consistency. In addition, the iHOT-12Sv demonstrated strong to very strong correlations with the HOS (Rho ranged from 0.741 to 0.827; p < 0.001) and the iHOT-33 (Rho = 0.932; p < 0.001), respectively; acceptable test-retest reliability (ICC = 0.86 to 0.94); SEM = 6.21 and MDC = 17.22; and no floor or ceiling effects were found. Conclusions: The iHOT-12Sv can be used as a valid and reliable tool for clinical evaluation of physically active patients with hip pathology. However, the full version is preferable for research purposes aiming to assess changes in hip function.